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Updated: Jan 22, 2026
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Identification and Quantification of Deranged Metabolites in Critically Ill Patients Using NMR-Based Metabolomics
Published on: November 29, 2024
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Ascorbigen A-NMR identification.
Vladimír Sychrovský1, David Šaman1, Radovan Fiala2
1Institute of Organic Chemistry and Biochemistry of the CAS, Prague 6, Czech Republic.
Magnetic Resonance in Chemistry : MRC
|July 2, 2019
Summary
This study unambiguously determined the atomic connectivity of ascorbigen A for the first time using advanced NMR techniques. The confirmed structure aligns with previous suggestions, advancing our understanding of this important metabolite.
Area of Science:
- Organic Chemistry
- Metabolomics
- Structural Elucidation
Background:
- Ascorbigen A is an important metabolite with an incompletely defined structure.
- Previous structural suggestions for ascorbigen A were made in 1966.
- Unambiguous determination of ascorbigen A's atomic connectivity is crucial for understanding its biological role.
Purpose of the Study:
- To unambiguously determine the complete atomic connectivity of ascorbigen A.
- To confirm the stereochemistry of ascorbigen A using spectroscopic and computational methods.
- To validate the previously proposed structure of ascorbigen A.
Main Methods:
- Two-dimensional Nuclear Overhauser Effect SpectroscopY (2D INADEQUATE) for carbon-carbon connectivity.
- Correlation SpectroscopY (COSY) and gradient Heteronuclear Single Quantum Coherence (gHSQC) for C-C and C-H bond identification.
- Proton Nuclear Magnetic Resonance (1H NMR) and Density Functional Theory (DFT) calculations for structural and stereochemical analysis.
Main Results:
- Complete atomic connectivity of ascorbigen A was established for the first time.
- The derived structure, 3-((1H-indol-3-yl)methyl)-3,3a,6-trihydroxytetrahydrofuro[3,2-b]furan-2(5H)-one, confirmed the 1966 proposal.
- DFT calculations and Nuclear Overhauser Effect (NOE) measurements helped elucidate the stereochemistry, identifying two potential isomers, with one excluded on synthetic grounds.
- Rotational flexibility and solvent model limitations impacted detailed DFT NMR interpretation.
Conclusions:
- The structure of ascorbigen A has been unambiguously determined and confirmed.
- The study provides a detailed stereochemical assignment for ascorbigen A.
- This work enhances the understanding of ascorbigen A's chemical structure and properties.
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